EF Code First:IValidatable Object未验证

Question

我在一个简单的测试场景中有一个对象,它使用EF Code First并实现IValidatableObject.有一些非常简单的逻辑可以添加验证错误并将其返回.对象上还有其他验证.

但是,在保存对象时 - 基于属性的验证工作 - IValidatableObject接口似乎永远不会触发.调试器不会进入它,并且调用SaveChanges()或GetValidationErrors()时错误永远不会出现.

public class Customer : IValidatableObject {
[Key]
public int Id { get; set; }

[StringLength(50)]
[DisplayName("First Name")]

public string FirstName { get; set; }

[Required]
[DisplayName("Last Name")]
[StringLength(50)]
public string LastName { get; set; }

[Required]
[StringLength(100)]
public string Company { get; set; }

[StringLength(200)]
public string Email { get; set; }

[DisplayName("Credit Limit")]
public decimal CreditLimit { get; set; }

[DisplayName("Entered On")]
public DateTime? Entered { get; set; }


public virtual ICollection<Address> Addresses { get; set;  }


public Customer()
{
    Entered = DateTime.Now;
    CreditLimit = 1000.00M;

    Addresses = new List<Address>();
}

public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
{
    var results = new List<ValidationResult>();

    // add an error ALWAYS for testing - it doesn't show up
    // and the debugger never hits this code
    results.Add(new ValidationResult("Validate Added message",new [] { "Company" }));

    return results;
}

当我现在尝试添加客户并检查验证错误时:

public void AddNewCustomer()
{
    Customer customer = new Customer();  

    context.Customers.Add(customer);

    customer.LastName = "Strahl";
    customer.FirstName = "Rick";
    customer.Entered = DateTime.Now;
    //customer.Company = "West Wind"; // missing causes val error

    var errorEntries = context.GetValidationErrors();
}

我得到了一个公司的验证错误,但是IValidatableObject中的任何内容都应该总是失败.

知道为什么吗？

Answer 1

引用杰夫汉德利关于验证对象和属性的博客文章与验证器:

验证对象时,Validator.ValidateObject中应用以下过程:

1. 验证属性级属性
2. 如果任何验证器无效,则中止验证返回失败
3. 验证对象级属性
4. 如果任何验证器无效,则中止验证返回失败
5. 如果在桌面框架上并且该对象实现了IValidatableObject,则调用其Validate方法并返回任何失败

这表明您尝试做的事情不会开箱即用,因为验证将在步骤#2中止.